I spent too many hours yesterday trying to beat Cygwin and Rake into submission. All because of the horror of backslashes etc.
Cygwin mostly works, but there are always corner cases. Well Flex seems to be one of them. I am by no means a Cygwin expert - perhaps I should learn more.
Anyways, here is a tip. Don't even try to feed the Flex compiler (mxmlc) path names like /cygdrive/c/flex_2_sdk_2 or path it any config file references using this style.
You must instead do things like:
Anyways, no big deal of course.
This type of panic is only typically an issue when you are dealing with a new tool. This is why I love the project "Work Instructions" wiki page. This is the step by step instructions for the new developer (or you when you get a new machine) that tells you exactly what to do to get productive quick. Even better - a team starter VmWare image or some such.